Spatial Water Quality Assessment and Mapping of Lahan Swamp, Chaiyaphum, Thailand

Lahan Swamp is important as a national wetland of Thailand, providing water for nearby agriculture, fisheries and even people in Chaiyaphum municipality. Water samples from eight monitoring sites in Lahan Swamp were collected in November 2009, January, March, May and August, 2010 and analyzed for temperature, pH, salinity, Dissolved Oxygen (DO), turbidity, transparency, Total Dissolved Solids (TDS), Biochemical Oxygen Demand (BOD), ammonia-nitrogen (NH3-N), nitrite-nitrogen (NO2-N), nitrate-nitrogen (NO3-N), Total Phosphorus (TP), Coliform bacteria and E. coli. Then all data were used to produce water quality maps with the ArcGIS program. The results classified water quality of Lahan Swamp at class 2, as described by The Pollution Control Department of Thailand, suitable for consumption but requiring special water treatment. However, the water can be used for fishing, swimming, and water sports. Yet, in some months, water qualities at Lam Kunchoo, Klong Sansab, Shrine-pump station, and Don Lanam village were poor with BOD values at 6.1, 6.6, 7.0, and 7.8 mg/L, respectively. They were categorized as class 5 thus should only be used for navigation. Since the human community and industrial areas are growing around Lahan swamp, wastewater treatment regulation and fishery restriction will be needed to protect water quality in this swamp.